Will Old Testament saints appear before the judgment seat of Christ? If not, is there a similar judgment they will appear before?
The word "Christ" in the "judgment seat of Christ," means "Messiah, the anointed one." Since Christ is the judge and king, very likely he is the member of the Godhead that OT saints would stand before.
There is not an explicit statement but it makes sense that he would conduct the judgment of OT saints as well as NT saints.
This article on our website might be of some help to you as well.
For more information on the subject of Heaven, see Randy Alcorn’s book Heaven.